You are here:
Impact of Food Waste Diversion on Landfill Emissions
Citation:
Jordan, P., M. Krause, G. Chickering, D. Carson, AND T. Tolaymat. Impact of Food Waste Diversion on Landfill Emissions. Global Waste Management Symposium, Indian Wells, California, February 23 - 26, 2020.
Impact/Purpose:
Food waste diversion is becoming more common at municipalities across the country. Food waste contributes a large portion of the moisture content and methane generation potential to the municipal solid waste streams entering landfills. This research explores how removing food waste from lab-scale landfills will impact the quality and quantity of liquid and gas emissions. This information is important for landfill operators and regulators as they explore these options.
Description:
Food waste has long been a major component of the municipal solid waste (MSW) stream in the United States. Many states have recently established recycling goals or organics management policies that would necessitate the diversion of food waste from landfills to other management schemes such as composting or anaerobic digestion. Food wastes can be heterogenous and chemically complex, affecting landfill environments in unique ways. Food waste has also been understood to degrade relatively quickly, before landfill gas collection infrastructure can be installed, and so most food waste methane is assumed to be emitted. Five lysimeters (laboratory-scale landfills) were constructed with decreasing levels of food waste to simulate a range of scenarios that diverted 0, 25, 50, 75, and 100% food waste from the landfill-bound MSW stream. The objective was to identify the changes to rate and volume of landfill gas generation and the chemical characteristics of leachate (landfill wastewater). Landfills that diverted 100 or 75% of food waste began generating methane the fastest, contradictory to how current models predict landfill methane generation. This was found to be because food wastes contribute volatile fatty acids to MSW, that lowers pH and delays microbial methanogen dominance. Landfill leachate from landfills that diverted 100 or 75% of the food waste also had significantly decreased ammonia levels compared to the other lysimeters, which could reduce wastewater treatment costs.